Substituted pyridinyloxy(thio)phenyl -acetamides, -ureas and urea derivatives

ABSTRACT

Disclosed are novel substituted pyridinyloxy(thio)phenyl-acetamides, -ureas and urea derivatives, N-oxide derivatives thereof, and certain novel intermediates therefore. The compounds of the instant invention are useful as herbicides and can be formulated to provide herbicidal compositions.

SUMMARY OF THE INVENTION

The present invention is directed to substitutedpyridinyloxy(thio)phenyl -acetamides, -ureas and urea derivativescorresponding to the formula: ##SPC1##

Wherein: ##EQU1## r represents an integer of 4 or 5; Q REPRESENTS ANINTEGER OF 0 TO 2, INCLUSIVE;

Each p independently represents an integer of 0 or 1;

Each X independently represents bromo, chloro, iodo or fluoro;

m represents an integer of 0 to 4, inclusive;

Each Y independently represents cyano, nitro, ZR³,--C(X')₃ or ##EQU2## nrepresents an integer of 0 to 2, inclusive; EACH Z independentlyrepresents oxygen or sulfur;

Q represents methyl, ethyl, halo, nitro, cyano or trifluoromethyl;

Each X' independently represents hydrogen or halo;

Each R independently represents hydrogen or an alkyl group of from about1 to about 3 carbon atoms;

R¹ represents hydrogen, an alkyl group of from about 1 to about 4 carbonatoms or an alkoxy group of from about 1 to about 4 carbon atoms;

R² represents an alkyl group of from about 1 to about 3 carbon atoms or##SPC2##

R³ represents an alkyl group of from about 1 to about 3 carbon atoms;

R⁴ and R⁵ each independently represents hydrogen or an alkyl group offrom about 1 to about 4 carbon atoms; and

Each R⁶ represents halo or an alkyl group of from about 1 to about 3carbon atoms.

For the sake of brevity and simplicity, the term "active ingredient" isused hereinafter in this specification to broadly describe the compoundsof the present invention. In the reaction sequences set forth below, allsubstituents, unless otherwise expressly indicated, are the same as setforth above.

The active ingredients of the present invention are normally crystallinesolids and are soluble in the usual organic solvents, as well as havingsome solubility in water. The active ingredients are useful as plantgrowth regulants, and especially as herbicides when applied either as apre-emergence or post-emergence treatment and may be formulated with theusual herbicide carriers for use in controlling unwanted plants.

DETAILED DESCRIPTION

The active ingredients of the present invention are useful asherbicides, particularly as post-emergent herbicides. Several of theactive ingredients of the present invention have been found suitable forcontrolling unwanted plants among crops such as, for example, soybeans,corn and rice, without injuring the crops. As used in the presentspecification and claims, the term "herbicide" means an activeingredient which, when used in a growth controlling amount, controls ormodifies the growth of plants. By a "growth controlling amount" is meantan amount of compound which causes a modifying effect upon the growth ofplants. Such modifying effects include all deviations from naturaldevelopment, for example, killing, retardation, defoliation,desiccation, regulation, stunting, tillering, and the like. By "plants"it is meant germinant seeds, emerging seedlings, and establishedvegetation, including the roots and above-ground portions.

The term "alkyl" is used herein and in the appended claims to designatea straight or branched chain alkyl radical containing from 1 to about 4carbon atoms, such as, for example, methyl, ethyl, propyl, isopropyl,butyl, isobutyl and tert-butyl. The term "alkoxy" as employed designatesa straight or a branched-chain radical containing from 1 to about 4carbon atoms, such as, for example, methoxy, ethoxy, propoxy,isopropoxy, butoxy, isobutoxy and tertbutoxy.

The terms "halo" and "halogen" are employed herein to representchlorine, fluorine and bromine.

Preferred compounds of the present invention are those compounds whereinn is 0 and m is at least 1. In a further preferred embodiment, m is 0and n is at least 1. Another preferred class of compounds are thosewherein the sum of m + n is one and X or Y is ring substituted in the6-ring position of the pyridine moiety. In another embodiment, thosecompounds wherein the sum of m + n is at least two are preferred. In anadditional preferred embodiment, T is R³. Another class of preferredcompounds includes those wherein T is ##EQU3## A further class ofpreferred compounds includes those wherein T is ##EQU4## and R¹ and R²each represent alkyl. Still another preferred class of compoundsincludes those wherein T is ##EQU5## R¹ is alkoxy and R² is alkyl. Anadditional preferred class is directed to compounds wherein T is##EQU6## m is 1, n is 0 and X is in the 6-ring position of the pyridinemoiety. A further preferred class of compounds are those wherein T is##EQU7## n is 1, m is O and Y is in the 6-ring position of the pyridinemoiety. In still another preferred embodiment, T is ##EQU8##

The active ingredients of the present invention are prepared by avariety of methods. The active ingredients wherein T is R³ (i.e., alkylof from 1 to about 3 carbon atoms), which are hereinafter referred to as"acetamide" compounds, can be prepared by reacting an appropriatelysubstituted halopyridine with a selected sodium acetamidophenatereactant in the presence of an inert solvent under reflux conditions.Such reaction can be represented schematically as follows: ##SPC3##

Reaction I

Reaction I proceeds readily under ambient atmospheric pressure attemperatures of from about 90° to about 150°C. A solution of the sodiumacetamidophenate reactant in methanol is added portionwise, ordinarilydropwise, to a solution of the substituted halopyridine reactant in aninert solvent such as, for example, dimethylsulfoxide,hexamethylphosphoramide, dimethylformamide, and the like. Stoichiometricproportions of the reactants are usually employed.

The sodium acetamidophenate solution, which can be prepared by rapidlyadding stoichiometric proportions of acetamidophenol to a solution ofsodium metal in dry methanol, is usually added dropwise to awell-stirred solution of halopyridine over a peroid of from about 30 toabout 90 minutes. The reactants are usually mixed at ambienttemperatures and heated to the refluxing temperature of the mixture,which is thereafter maintained for a period of time sufficient tosubstantially complete the reaction. Depending upon the rate ofreaction, the reaction mixture may be refluxed for a period of time fromabout one to about eight hours. Following the completion of thereaction, the reaction mixture is allowed to cool, mixed with ice waterand the resulting precipitate filtered off, washed again with water anddried. The so-dried reaction product can be employed as such in furtheroperations or further purified by recrystallization from a solvent orsolvent mixture, such as, for example, benzene/hexane, benzene/methylenechloride and the like.

The active ingredients of the present invention wherein T is --NR¹ R²(wherein R¹ and R² are hydrogen or alkyl and all other substitutents areas previously defined, conveniently hereinafter referred to as "phenylurea" compounds), are, with the exception of the N-oxide derivativesthereof, readily prepared by converting the acetamide products ofReaction I to a corresponding amine intermediate. Such amineintermediates are novel and hence are considered an integral part of thepresent invention. The novel amine intermediates, which can be obtainedby refluxing the acetamide products of reaction I with borontrifluoridein the presence of methanol, are reacted with an appropriatelysubstituted (thio)-carbamoyl halide reactant, such as a carbamoylchloride, in the presence of pyridine to form the corresponding phenylurea compounds. The reaction can be schematically represented asfollows: ##SPC4##

Reaction II

The reaction to convert the acetamide products to the correspondingamine intermediates (step a, Reaction II) proceeds readily under ambientatmospheric pressure and at the reflux temperature of the reactionmixture. In such operations, the acetamide product is mixed with asolution of borontrifluoride in methanol and the resulting reactionmixture is heated to the refluxing temperature of the mixture for aperiod of from about 2 to about 3 hours. An excess of borontrifluorideis usually employed. The methanol solvent is then usually distilled offand the concentrated reaction mixture is cooled, poured into cold waterand treated with concentrated aqueous ammonia until the solution isbasic. The resulting product precipitate is recovered by filtration,washed and recrystallized if desired from a solvent such as, forexample, benzene, methylene chloride and the like. The aqueous filtrateremaining after recovery of the product precipitate can also beextracted with such solvents to recover additional quantities of thedesired amine product.

The amine intermediates prepared above are, in step b of Reaction II,reacted with an appropriately substituted carbamoyl halide reactant inthe presence of dry pyridine to obtain the desired phenyl urea compoundsof the instant invention. The reaction proceeds readily under ambienttemperature and pressure conditions. Generally, stoichiometric amountsof the reactants are employed. In carrying out the reaction, the totalquantity of the carbamoyl halide reactant is usually added all at onceto a solution of the amine reactant in pyridine and the resultingreaction mixture allowed to stand at ambient temperatures for a periodof from about 15 to about 30 hours. The reaction mixture is then pouredinto cold water and allowed to stand for a short period of time. Theresulting product precipitate is recovered by filtration and mixed witha solvent, such as one of those hereinbefore mentioned. The resultingsolvent-product solution is dried, treated with norite and concentratedby evaporation to crystallize out the desired phenyl urea product.

The N-oxide derivatives of the above "phenylurea" compounds are usuallyprepared by other methods in view of the high reactivity of the N-oxide(.tbd.N→O) group with certain reagents, such as the borontrifluoridereagent employed in step (a) of Reaction II. In such method, the salt ofa selected substituted amino(thio)phenol reactant of the formula:##SPC5##

is reacted with the N-oxide derivative of a selected substitutedhalopyridine reactant to obtain the N-oxide form of the desiredpyridinyloxy(thio)benzenamine intermediate. The latter reaction iscarried out employing procedures analogous to those employed in ReactionI above. The benzenamine intermediate can be reacted with a carbamoylhalide reactant as in step (b) of Reaction II to obtain the desiredN-oxide derivatives of the pyridinyloxy(thio)phenylurea compounds of thepresent invention.

In other procedures, the above amino(thio)phenol reactant can be reactedwith a selected carbamoyl halide reactant, as in step (b) of ReactionII, to obtain a corresponding hydroxy- or mercapto- phenylurea reactant.The thus-obtained phenylurea reactant can be reacted with an N-oxidehalopyridine reactant in the presence of a base, such as, for example,sodium metal in methanol, sodium hydroxide or the like, and a solventcarrier, such as previously mentioned herein, at temperatures ordinarilyranging from about 20° to about 80°C. or higher for a period generallyfrom about 1 to about 6 or more hours. The desiredpyridinyloxy(thio)phenylurea-1-oxide derivative is recovered in a mannersimilar to recovery procedures previously set forth.

The N-oxide derivatives of the halopyridine reactants employed above asstarting materials are prepared according to conventional oxidativeprocedures. In typical known types of operations, the selectedhalopyridine reactant is treated with anhydrous trifluoroacetic acid andexcess 90% hydrogen peroxide under reflux conditions to obtain thedesired N-oxide derivative.

The novel amine intermediates employed in Reaction II can also beemployed in alternative procedures for the preparation of the acetamidecompounds of the instant invention. In such operations, a selectedsubstituted amine intermediate is reacted with a selected substitutedacid halide, such as, for example, acetyl chloride, propionyl chloride,butyryl chloride and the like. The reaction is carried out by mixing thereactants, ordinarily in stoichiometric proportions, in the presence ofan inert solvent, such as, for example, pyridine, and maintaining theresulting reaction mixture at ambient temperatures for a period of fromabout 16 to about 24 hours. The reaction mixture is then mixed with coldwater and the resulting product precipitate recovered and purified inprocedures analogous to those set forth for Reaction I.

The novel amine intermediates described above in relation to ReactionII, with the exception of the N-oxide derivatives thereof, can also beprepared in alternative procedures whereby a selected salt of anitro(thio)phenol is reacted with an appropriate substitutedhalopyridine compound to form the corresponding substitutednitrophenoxy- or nitrophenylthio- pyridine compound, which is thenreduced to the corresponding aminophenoxy or aminothiophenyl- pyridinecompound with a reducing agent, such as iron powder. This reaction canbe represented as follows: ##SPC6##

Reaction III

The reaction in step (a) of Reaction III proceeds readily under ambientatmospheric pressure at reaction temperatures of from about 100° toabout 160°C. for a period of from about 3 to about 5 hours. In suchoperations, the salt of the substituted nitrophenol or nitrothiophenolis mixed with the selected halopyridine reactant in the presence of aninert solvent, such as previously mentioned with respect to Reaction I,and the resulting reaction mixture heated at a temperature within theabove indicated ranges. Following the substantial completion of thereaction, the reaction mixture is cooled and mixed with cold water. Theresulting product precipitate is recovered by filtration andrecrystallized according to conventional techniques from a solvent suchas, for example, benzene, methylene chloride and the like.

The product thus obtained from step (a) of Reaction III is mixed, in thepresence of an aqueous alcohol solution, with a reducing agent, such as,for example, iron powder. The resulting reaction mixture is heated tothe reflux temperature thereof with vigorous stirring and an alcoholsolution of concentrated hydrochloric acid is added thereto,portionwise, over a 10 to 30 minute period. The reaction mixture is thenheated at the reflux temperature for a period of from about 2 to about 4hours and then filtered while hot. The solid product thus obtained iswashed with an aqueous alkanol solution, such as 50-95% ethanol, and thefiltrate portions combined and extracted with a solvent such as benzene,methylene chloride or the like. The extract is then dried, treated withactivated charcoal, such as Norite, filtered and evaporated to drynessto obtain the desired aminophenoxy- or aminothiophenyl- pyridine productas a crystalline solid or oily liquid.

The N-oxide derivatives of the benzenamine intermediates can also beprepared by first reducing the nitro(thio)phenol reactant to thecorresponding amino(thio)phenol reactant with a reducing agent as instep (b) of Reaction III and then reacting the salt of suchamino(thio)phenol reactant with the N-oxide derivative of thehalopyridine reactant employing procedures analogous to those set forthin Reaction I. Such alternative procedures are employed in this instancein view of the high reactivity of the N-oxide group with a reducingagent.

In still other procedures, the foregoing amino(thio)phenol reactant canbe reacted with phosgene or thiophosgene, as in step (a) of Reaction IV(hereinafter set forth), to obtain a correspondingphenyliso(thio)cyanate reactant which can be reacted (a) with a selectedsubstituted pyrrolidine or piperidine reactant, as in the followingReaction IV, to obtain a corresponding hydroxy- or mercaptophenyl(pyrrolidine- or piperidine-)carboxamide reactant or (b) with a selectedhydroxyl- or mercapto amine reactant, as in the following Reaction V, toobtain a corresponding hydroxy- or mercapto- phenylurea reactant. Thelatter carboxamide and phenylurea reactants can be reacted with anN-oxide halopyridine reactant in the presence of a base, such as, forexample, sodium hydroxide or sodium metal in methanol, and a solventcarrier, such as previously mentioned herein, at temperatures ordinarilyranging from about 20° to about 80°C. or higher for a period generallyfrom about 1 to about 6 or more hours. The desiredpyridinyloxy(thio)phenyl ((pyrrolidine- or piperidine-)carboxamide) or-urea products are recovered in a manner similar to the recoveryprocedures set forth hereinabove.

The pyrrolidine- and piperidine- carboxamide derivatives of the presentinvention, i.e., wherein T is ##EQU9## are prepared by reacting theamine intermediates of the present invention (prepared in step (a) ofReaction II or step (b) of Reaction III) with phosgene or thiophosgenein the presence of toluene to form a corresponding novel pyridinyloxy-or pyridinylthio- phenyl iso- or isothio- cyanate intermediate,hereinafter referred to as "isocyanate" intermediates, which is thenreacted with a selected pyrrolidine or piperidine reactant to obtain thedesired product. The essential steps of the reaction sequence can beschematically illustrated as follows: ##SPC7##

Reaction IV

The isocyanate intermediates are readily prepared according to step (a)above by first preparing a solution of phosgene or thiophosgene in asolvent such as, for example, water, toluene or the like, and thenrapidly adding, with stirring, a solution of the amine starting materialin toluene. The amine addition is regulated so as to maintain thetemperature of the mixture at about 5°C. or less, with additionalquantities of solvent being added if necessary. Following the completionof the amine addition, the reaction mixture is agitated and heatedgradually until a temperature of from about 75° to about 95°C. isreached. The solvent carrier is then removed from the reaction mixtureby evaporation under reduced pressure and the remaining residue taken upin hexane which is then cooled to crystallize the desired product. Anexcess of phosgene or thiophosgene, in a ratio of from about 3 to about4 moles thereof per mole of amine reactant, is preferably employed inthe reaction. During the reaction, excess phosgene can be removed bypurging the reaction mixture with an inert gas, such as nitrogen.

In step (b) of Reaction IV, the isocyanate intermediate is reacted withthe selected pyrrolidine or piperidine reactant under reactionconditions generally the same as for the hereinbefore describedprocedures in step (b) of Reaction II. Stoichiometric quantities of thereactants are usually employed.

The isocyanate intermediates prepared in step (a) of Reaction IV areemployed in the preparation of compounds of the instant inventionwherein T is ##EQU10## and R¹ is alkoxy and R² is alkyl. Other phenylurea compounds of the present invention can also be prepared from theisocyanate intermediates. In such operations, the isocyanateintermediates are reacted with an appropriately substituted hydroxylamine salt reactant in the presence of a base and an inert solvent, suchas, for example, triethylamine and pyridine according to the followingillustrative reaction sequence: ##SPC8##

Reaction V

The reaction is conducted under ambient atmospheric pressure attemperatures of from about 50° to about 100°C. Preferably, an actuatingagent is employed to increase to the reaction rate. Representativeactuating agents that can be employed include, for example, tertiaryamines such as triethylamine and the like. The reactants are usuallyemployed in stoichiometric proportions while an excess of the actuatingagent is employed.

In carrying out the reaction, the isocyanate and substitutedhydroxylamine reactants are contacted in the presence of a dry inertsolvent containing the actuating agent. Representative solvents include,for example, pyridine, toluene or the like. The resulting reactionmixture is heated with stirring at a temperature within the abovedescribed range for a period of from about one-half to about 2 or morehours. The reaction mixture is then stirred at ambient temperatures fora period of from about 1 to about 12 hours and then cooled and mixedwith cold water. The resulting product precipitate is recovered andpurified in typical procedures previously set forth.

The following examples illustrate the present invention and the mannerby which it can be practiced but, as such, should not be construed aslimitations upon the overall scope of the same.

EXAMPLE 1 N-(4-((6-bromo-2-pyridinyl)oxy)phenyl)acetamide

A solution of sodium methylate was prepared by adding sodium metal (1.6grams; 0.07 mole) to 50 milliliters (ml) of dry methanol.4-Acetamidophenol (10.6 grams; 0.07 mole) was added to the solution in arapid manner and the resulting solution of sodium 4-acetamidophenate wasthen added portionwise, over a period of about one hour, to an agitatedsolution of 2,6-dibromopyridine (6.6 grams; 0.07 mole) in 70 ml. ofdimethylsulfoxide. The reaction mixture was distilled during theaddition of the phenate solution to remove methanol and maintain thetemperature of the reaction mixture in the range of from about 126° toabout 132°C. Following the completion of the addition of the phenatesolution, distillation of the reaction mixture was stopped and thereaction mixture was allowed to stand at ambient temperatures for aperiod of about 16 hours. The reaction mixture was then refluxed forabout 21/4 hours at a temperature of about 127°C. and then cooled andpoured into ice water, stirred and the resulting solid precipitaterepresenting the desired N-(4-((6-bromo-2-pyridinyl)oxy)phenyl)acetamidecompound removed by filtration, washed and dried. The recovered productwas found to have carbon, hydrogen, nitrogen and bromine contents of50.4, 3.7, 9.08 and 27.56 percent, respectively, as compared with thetheoretical contents of 50.8; 3.6; 9.1 and 26.0 percent, respectively,calculated for the named structure.

EXAMPLE 2 N-(4-((6-chloro-2-pyridinyl)thio)phenyl)-acetamide

4-Acetamidothiophenol (16.8 grams; 0.1 mole) was mixed with a solutionof sodium methylate (prepared by mixing sodium metal (2.3 grams; 0.1mole) in 90 ml. of methanol) and the resulting sodium4-acetamidothiophenol solution added over a period of about one hour toa well-stirred solution of 2,6-dichloropyridine (14.8 grams; 0.1 mole)in 100 ml. of dimethylsulfoxide. The reaction mixture was distilledduring the addition and the reaction temperature maintained at about100°C. for this period and for a period of about two hours thereafter.The reaction mixture was then poured into 350 ml. of water and theresulting product precipitate recovered by filtration, washed severaltimes and taken up in 300 ml. of hot benzene and dried and treated withNorite. About 350 ml. of hexane was added to precipitate the productfrom the benzene solvent which was recovered by filtration. As a resultof such operations, the desiredN-(4-((6-chloro-2-pyridinyl)thio)-phenyl)acetamide compound wasrecovered as a crystalline solid which was found to have carbon,hydrogen, nitrogen, chlorine and sulfur contents of 56.2, 4.3, 9.9, 11.4and 11.63 percent, respectively, as compared with the theoreticalcontents of 56.0, 3.96, 10.05, 12.7 and 11.45, respectively, calculatedfor the named structure.

EXAMPLE 3 N-(3-chloro-4-((6-chloro-2-pyridinyl)oxy)phenyl)propionamide

4-((6-Chloro-2-pyridinyl)oxy)-3-chlorobenzeneamine (7.1 grams; .028mole) and propionyl chloride (2.6 grams; .028 mole) were contacted inthe presence of 40 ml. of dry pyridine and the resulting reactionmixture allowed to stand at ambient temperatures for a period of about18 hours. The reaction mixture was then poured into 250 ml. of coldwater and allowed to stand for about 15 minutes. The resulting productprecipitate was recovered by filtration and taken up in boiling benzeneand the resulting solution dried, treated with Norite and filtered.Hexane was then added to the filtrate which was then cooled toprecipitate the desiredN-(3-chloro-4-((6-chloro-2-pyridinyl)oxy)phenyl)propionamide compound asa white crystalline solid having a melting point of 166°-168°C. Theproduct was found to have carbon, hydrogen, nitrogen and chlorinecontents of 55.0, 3.9, 9.0 and 22.5, respectively, as compared with thetheoretical contents of 54.0, 3.9, 9.0 and 22.8, respectively,calculated for the named structure.

EXAMPLE 4 N'-(4-((6-chloro-2-pyridinyl)thio)phenyl)-N,N-dimethyl urea

N-(4-((6-chloro-2-pyridinyl)thio)phenyl)acetamide (18.15 grams; 0.065mole) from Example 2 above was mixed with 220 ml. of a solution ofborontrifluoride (BF₃) in methanol (10 grams of BF₃ in 100 ml. ofmethanol) and the resulting reaction mixture was heated at the refluxtemperature of the reaction mixture for a period of two hours. Thereaction mixture was then cooled to about 0°C. and 105 ml. ofconcentrated aqueous ammonia added gradually, while maintaining thereaction mixture at from about 0° to about 5°C., until the reactionmixture was basic. Methanol and ammonia were then distilled off underreduced pressure and the residue containing the precipitated product wasrecovered by filtration and recrystallized from hexane. As a result ofthese operations, the desired 4-((6-chloro-2-pyridinyl)thio)benzenamineintermediate product was recovered as a crystalline solid which wasfound to have carbon, hydrogen, nitrogen, chlorine and sulfur contentsof 55.8, 3.9, 12.20, 15.1 and 13.3 percent, respectively, as comparedwith the theoretical contents of 55.7, 3.84, 11.72, 15.0 and 13.55percent, respectively, calculated for the named structure.

The benzenamine intermediate (6.85 grams; 0.029 mole) was mixed with 20ml. of dry pyridine and dimethyl carbamoyl chloride (3.1 grams; 0.029mole) was added thereto at ambient temperatures. The resulting reactionmixture was allowed to stand at ambient temperatures for a period ofabout 15 hours, following which it was poured into 200 ml. of coldwater. After standing for a few minutes, the resulting productprecipitate was recovered by filtration and recrystallized from toluene.The recovered N'-(4-((6-chloro-2-pyridinyl)thio)phenyl)-N,N-dimethylurea compound had a melting point of 187°-188°C. and was found to havecarbon, hydrogen, nitrogen, chlorine and sulfur contents of 54.8, 4.9,13.2, 11.42 and 10.4 percent, respectively, as compared with thetheoretical contents of 54.7, 4.58, 13.65, 11.55 and 10.4 percent,respectively, calculated for the named structure.

EXAMPLE 5 4-((6-fluoro-2-pyridinyl)oxy)benzenamine

A mixture of 2,6-difluoropyridine (20.2 grams; 0.175 mole) and drysodium p-nitrophenate (28.2 grams; 0.175 mole) in 130 ml. of drydimethylsulfoxide was heated at a temperature of about 110°C. for aperiod of about 4 hours. Following the completion of the reactionperiod, the reaction mixture was cooled, poured into 325 ml. of coldwater and allowed to stand for a few minutes. The resulting crystallizedproduct was recovered by filtration and recrystallized from a 50:50benzene-hexane mixture. The desired 2-fluoro-6(4-nitrophenoxy)pyridineintermediate (19.1 grams; 0.018 mole) which was obtained as acrystalline solid melting at 104°-105°C. and iron powder (15 grams;0.268 mole) were mixed in 115 ml. of 50 % aqueous ethanol and theresulting reaction mixture heated at the reflux temperature thereof.Concentrated hydrochloric acid (5.5 ml. in 20 ml. of 50% ethanol) wasadded thereto, portionwise, with vigorous stirring over a period ofabout 15 minutes. The reaction mixture was then refluxed for a period of3 hours, cooled, poured into water and neutralized with an aqueoussodium hydroxide solution. The resulting solid cake was recovered byfiltration and extracted with two 300 ml. portions of benzene. Theextracts were combined and treated with activated charcoal, filtered,and the filtrate evaporated to obtain the desired4-((6-fluoro-2-pyridinyl)oxy)benzenamine product as a white crystallinesolid having carbon, hydrogen and nitrogen contents of 65.2, 4.6 and13.9 percent, respectively, as compared with contents of 64.8, 4.4 and13.7 percent, respectively, calculated for the named structure.

EXAMPLE 6 4-((6-chloro-2-pyridinyl)oxy)phenyl isocyanate

A stream of phosgene was passed into 120 ml. of dry toluene maintainedat a temperature of about 0° to about 5°C. until a weight of 13.4 grams(0.135 mole) had been absorbed. 4-((6-Chloro-2-pyridinyl)oxy)benzenamine(10.0 grams; 0.045 mole) in 100 ml. of dry toluene was then added to thestirred phosgene solution over a period of about 15 minutes whilemaintaining the reaction temperature within a range of about 2° to about5°C. Following the completion of the addition, the reaction mixture wasstirred for about 20 minutes and the reaction temperature then graduallyraised as excess phosgene was purged with a stream of nitrogen. When areaction temperature of about 85°C. was attained, the reaction mixturebecame clear. The toluene solvent was then substantially removed underreduced pressure and hexane added to the residue to give the desired4-((6-chloro-2-pyridinyl)oxy)phenyl isocyanate product as a whitecrystalline product having a melting point of 96°-97° C.

EXAMPLE 7 4-((6-chloro-2-pyridinyl)oxy)phenyl isothiocyanate

Thiophosgene (10.5 grams; 0.091 mole) was added to an agitated solutionof water (170 ml.) and dimethoxyethane (25 ml.)4-((6-Chloro-2-pyridinyl)oxy)benzenamine (20 grams; 0.0906 mole) wasadded in small portions (the dimethoxyethane aids in suspending theamine in the aqueous thiophosgene solution) to the stirred thiophosgenesolution over a 20 minute period. The reactive temperature during theaddition was 25°-30°C. Following the addition of the amine reactant, thereaction mixture was filtered to recover the product precipitate whichformed during the reaction. The precipitate was then dissolved inboiling hexane and the resulting solution dried and cooled to give thedesired 4-((6-chloro-2-pyridinyl)oxy)phenyl isothiocyanate product as alight yellow crystalline solid having a melting point of 59°-62°C. Theproduct was found to have carbon, hydrogen, nitrogen, chlorine andsulfur contents of 55.5, 2.3, 10.9, 13.36 and 12.34 percent,respectively, as compared with the theoretical contents of 54.82, 2.69,10.66, 13.5 and 12.2 percent, respectively, calculated for the namedstructure.

EXAMPLE 8N-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-2,5-dimethyl-1-pyrrolidinecarboxamide

2,5-Dimethylpyrrolidine (2.5 grams; 0.0284 mole) was added at ambienttemperature to a solution of 4-((6-chloro-2-pyridinyl)oxy)phenylisothiocyanate, prepared as in Example 7 (7.0 grams; 0.0284 moles) in 25ml. of dry pyridine. The resulting reaction mixture was allowed to standat ambient temperatures for a period of about 16 hours and then pouredinto 300 ml. of cold water. The resulting product precipitate wasrecovered by filtration, washed with water and taken up in boilingbenzene. Hexane was then added to the solution and the solution cooledto precipitate the desiredN-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-2,5-dimethyl-1-pyrrolidinecarboxamide compound as a crystalline solid having a carbon, hydrogen,nitrogen and chlorine content of 62.2, 5.7, 11.9 and 10.2 percent,respectively, as compared with contents of 62.5, 5.82, 12.5 and 10.25percent, respectively, calculated for the named structure.

EXAMPLE 9 N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N-methoxy-N-methylurea

4-((6-chloro-2-pyridinyl)oxy)phenyl isocyanate (4.0 grams; 0.0162 mole),prepared according to Example 6, and N-methyl-O-methyl hydroxylaminehydrochloride (1.6 grams; 0.0162 mole) were added to 25 ml. of drypyridine containing 5.0 grams of triethylamine actuating agent. Theresulting reaction mixture was heated intermittently to about 60°C. overa period of about one-half hour and then poured into cold water. Theresulting precipitate, representing the desiredN'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N-methoxy-N-methyl ureacompound, was recovered by filtration and recrystallized from benzene.The crystalline product thus obtained was found to have a melting pointof 96°-97°C., and carbon, hydrogen, nitrogen and chlorine contents of54.7, 4.8, 13.7 and 11.64 percent, respectively, as compared to thetheoretical contents of 54.6, 4.58, 13.65 and 11.55 percent,respectively, calculated for the named structure.

EXAMPLE 10N-((4-chlorophenyl)thio)-N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N-methylurea

4-Chlorobenzenesulfenyl chloride (8.68 grams; 0.0496 mole) was addedover a period of about 3 minutes to a solution of N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl-N-methylurea (8.3 grams; 0.03mole) in 50 ml. of dry pyridine. The resulting reaction mixture wasstirred at a temperature of about 30°C. for a period of about one andone-half hours and then poured into 250 ml. of cold water. The resultingsticky product precipitate was dissolved in hot hexane, reprecipitatedtherefrom upon standing and the light-yellow, slightly sticky productobtained triturated with a small amount of cold acetonitrile. Filtrationof the mixture gave the desiredN-((4-chlorophenyl)thio)-N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N-methylureacompound as a white crystalline solid melting at 106°-109°C. The productwas found to have carbon, hydrogen, nitrogen, chlorine and sulfurcontents of 54.2, 3.5, 9.86, 17.0 and 7.46 percent, respectively, ascompared with contents of 54.3, 3.6, 10.0, 16.87 and 7.6 percent,respectively, as calculated for the named structure.

EXAMPLE 11 N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea-1-oxide

Dry powdered sodium hydroxide (2.44 grams; 0.061 mole) was dissolved in110 ml. of warm dimethylsulfoxide and N'-(4-hydroxyphenyl)-N,N-dimethylurea (11.0 grams; 0.061 mole) and 2,6-dichloropyridine-N-oxide addedthereto. The reaction mixture was stirred at a temperature of about60°C. for a period of five and one-half hours. After this period, aboutthree-fourths of the solvent carrier was removed by vacuum distillationand the residual oil thus obtained poured into ice water. The aqueousmixture was extracted with three 250 ml. portions of warm methylenechloride and the extracts combined. Evaporation of the solvent from theextract left a brown, syrupy residue which was washed with cold waterand then with dry benzene to give the desiredN'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea-1-oxidecompound as a crystalline solid melting at 190°-191°C. and havingcarbon, hydrogen, nitrogen and chlorine contents of 53.83, 4.63, 13.25and 12.78 percent, respectively, as compared with contents of 54.64,4.58, 13.65 and 11.52 percent, respectively, calculated for the namedstructure.

Other urea compounds and derivatives are similarly prepared fromselected substituted amine or isocyanate intermediates in accordancewith the procedures of Examples 4, 8, 9, 10 and 11 and the foregoingteachings of the specification. Such other compounds include, interalia, the following:

N'-(4-((3,5,6-trichloro-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea(184°-185°C.);

N'-(4-((6-fluoro-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea(149°-153°C.);

N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea (132°C.);

N'-(4-((6-(trifluoromethyl)-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea(121°-123°C.);

N'-((3-(6-fluoro-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea(131°-132°C.);

N'-(4-((6-methoxy-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea(132°-140°C.);

N'-(3-((6-(trifluoromethyl)-2pyridinyl)oxy)phenyl)-N,N-dimethyl urea(119°-120°C.);

N'-((3-(6-chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea(121°-123°C.);

N'-((4-(5-cyano-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea (143°C.);

N'-(4-((3,5-dichloro-6-fluoro-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea(170°-173°C.);

N'-(4-((4,6-bis(trifluoromethyl)-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea (133°-135°C.);

N'-((3-(5-chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea (98°-99°C.);

N'-(4-((6-fluoro-2-pyridinyl)oxy)phenyl)-N,N-dimethylthio urea(155°-160°C.);

N'-((4-(6-fluoro-2-pyridinyl)oxy)phenyl)-N-methylurea (161°-163°C.);

N'-((4-(6-cyano-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea (163°-165°C.);

N'-(4-((6-bromo-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea(144.5°-146.5°C.);

N'-(4-((5-chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea (130°-131°C.);

N,N-dimethyl-N'-(4-(2-pyridinyloxy)phenyl)urea (165°-167°C.);

N'-(4-((6-chloro-4-(trifluoromethyl)2-pyridinyl)oxy)phenyl)-N,N-dimethylurea(149.5°-150.5°C.);

N,N-dimethyl-N'-(4-((5-nitro-2-pyridinyl)oxy)phenyl)-urea;

N,N-dimethyl-N'-(4-((6-(methylthio)-2-pyridinyl)oxy)phenyl)urea(126°-129°C.);

N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N,N-diethylurea (162°-163°C.);

N'-(4-((3-chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea (163°-165°C.);

N'-(4-((3,5-dichloro-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea(160.3°-161.3°C.);

N,N-dimethyl-N'-(4-((6-methyl-2-pyridinyl)oxy)phenyl)urea (128°-131°C.);

N,N-dimethyl-N'-(4-((3,6-dichloro-2-pyridinyl)oxy)phenyl)urea(147°-150°C.);

N'-(4-((6-chloro-5-cyano-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea;

N'-(4-((6-chloro-2-pyridinyl)thio)phenyl)-N,N-dimethylurea(187°-188°C.);

N'-(4-((5-chloro-6-cyano-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea;

N'(4-((6-(chlorodifluoromethyl)-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea(138°-139°C.);

N'-(4((6-bromo-2-pyridinyl)oxy)phenyl)-N-methoxy-N-methylurea(95°-100°C.);

N'-(4-((6-fluoro-2-pyridinyl)oxy)phenyl)-N-methoxy-N-methylurea(111°-113°C.);

N'-(4-((4-chloro-6-trifluoromethyl)-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea(179°-184°C.);

N'-(4((6-chloro-4-(trifluoromethyl)-2-pyridinyl)oxy)phenyl)-N-methoxy-N-methylurea(137°-140°C.);

N-methoxy-N-methyl-N'-(4-(((6-trifluoromethyl)-2-pyridinyl)oxy)phenyl)urea(115°-117°C.);

N'-(4-((3-cyano-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea (179°-180°C.);

N,N-dimethyl-N'-(4-((6-(propylthio)-2-pyridinyl)oxy)phenyl)urea(129.7°-132.2°C);

N'-(4-((6-chloro-2-pyridinyl)oxy)-3-(trifluoromethyl)phenyl)-N,N-dimethylurea(142°-143°C.);

N,N-dimethyl-N'-(4-((6-(trifluoromethyl)-2-pyridinyl)thio)phenyl)urea(195°-197°C.);

N,N-dimethyl-N'-(4-((6-propoxy)-2-pyridinyl)oxy)phenyl)urea(118°-122°C.);

N'-(4-((6bromo-2-pyridinyl)thio)phenyl)-N,N-dimethylurea(157.5°-161.5°C.);

N'-(4-((6-chloro-2-pyridinyl)thio)phenyl)-N-methoxy-N-methylurea(140°-142°C.);

N'-(4-((6-fluoro-2-pyridinyl)thio)phenyl)-N,N-dimethylurea(154°-156°C.);

N-butyl-N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N-methylurea(99°-101°C.);

N-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-2,5-dimethyl-1-pyrrolidinecarboxamide(127°-130°C.);

N,N-dimethyl-N'-(4-(4-methyl-2-pyridinyl)oxy)phenyl)urea (158°-160°C.);

N'-(4-((4,6-dimethyl-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea;

N'-(4-((5-chloro-6-cyano-2-pyridinyl)oxy)phenyl)-N-methoxy-N-methylurea(141°-143°C.);

N'-(4-((5-chloro-6-cyano-2-pyridinyl)thio)phenyl)-N,N-dimethylurea(195°-198°C.);

N'-(4-((6-chloro-4-(chlorodifluoromethyl)-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea(165°-166°C.);

N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethylthiourea(135°-138°C.);

N'-(4-((6-iodo-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea (109°-112°C.);

N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N-methoxy-N-methylthiourea(125°-127°C.);

N-butyl-N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N-methylthiourea(77°-79°C.);

N'-(4-((6-bromo-2-pyridinyl)oxy)phenyl)-N,N-dimethylthiourea(141.5°-142.5°C.);

N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea-1-oxide (M.P.190°-191°C.);

N-butoxy-N'-(4-((3,4,5,6-tetrabromo-2-pyridinyl)thio)phenyl)-N-methylurea;

N-methoxy-N-propyl-N'-(3-((4-pyridinyl)oxy)phenyl)-thiourea;

N-((3,4,5-trichlorophenyl)oxy)-N'-(3-((4-chloro-6-amino-2-pyridinyl)oxy)phenyl)-N-methylurea;

N'-(3-((2,6-dicyano-4-pyridinyl)oxy)-4-ethylphenyl)-N-methoxy-N-methylurea;

N'-(4-((6-(trifluoromethyl)-3-pyridinyl)thio)-3-cyanophenyl)-N,N-ethylurea;

N-butyl-N'-(4-((5-(dichloromethyl)-3-pyridinyl)oxy)-2-nitrophenyl)-N-propylurea;

N'-(5-((2-bromo-6-methylamino-4-pyridinyl)thio)-3-bromophenyl)-N-butyl-N-methylthiourea;

N-butoxy-N'-(3-((5-(dichloromethyl)-3-pyridinyl)oxy)-4-cyanophenyl)-N-propylurea;

N'-(4-((4-methyl-3,5,6-trichloro-2-pyridinyl)thio)-3-methylphenyl)-N,N-dimethylurea;

N'-(4-((4,5-dimethyl-3,6-dichloro-2-pyridinyl)oxy)-3-fluorophenyl)-N-methyl-N-methoxythiourea;

N-(4-((4,6-dinitro-2-pyridinyl)oxy)phenyl)-3-propyl-1-piperidinecarboxamide;

N-(4-((5-chloro-2,6-dimethoxy-4-pyridinyl)oxy)-3-chlorophenyl)-2,6-dimethyl-1-piperidinethiocarboxamide;

N'-(5-((6-bromo-4-n-butylamino-2-pyridinyl)thio)-3-(trifluoromethyl)phenyl)-N-ethoxy-N-methylthiourea;

N'-(3-((6-chloro-4-di-n-butylamino-5-methyl-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea;

N-(4-((5,6-dichloro-3-cyano-4-propoxy-2-pyridinyl)thio)-2-chlorophenyl)-1-pyrrolidinecarboxamide;

N'-(4-((2,6-diamino-3,5-dichloro-4-pyridinyl)oxy)phenyl)-N,N-dimethylurea;

N'-(5-((6-chloro-4,5-dinitro-2-pyridinyl)thio)-3-methylphenyl)-N,N-di-n-propylurea;

N-((3,5-di-i-propylphenyl)oxy)-N'-(4((2,6-bis(trifluoromethyl)-4-pyridinyl)oxy)-N-methylthiourea;

N'-(4-((3,5,6-trichloro-4-(difluoromethyl)-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea;

N'-(3-((5-bromo-3,6-dichloro-4-(trifluoromethyl)-2-pyridinyl)thio-2-methylphenyl)-N-methylurea;

N'-(4-((2,6-di-(dimethylamino)-4-pyridinyl)thio)phenyl)-N-methoxy-N-methylthiourea;

N-(4-((3,4,5,6-tetrachloro-2-pyridinyl)oxy)phenyl)-1-pyrrolidinecarboxamide and

N'-(4-((4-cyano-6-(trifluoromethyl)-2-pyridinyl)thio)phenyl)-N,N-dimethylthiourea.

The novel amine and isocyanate intermediates which are employed, interalia, to prepare the foregoing are readily apparent in view of thespecific enumerated compounds. Such amine intermediates are of theformula represented in Reaction Sequences III and IV of thespecification and are prepared in accordance with the teachings of thespecification and the foregoing Examples 4, 5 and 6. The nomenclaturefor such compounds is as set forth in such examples. The novelisocyanate intermediates employed to prepare, inter alia, theabove-enumerated compounds are likewise readily apparent in view of theabove-enumerated compounds as well as the amine intermediates usedtherein and from which the isocyanate intermediates are themselvesprepared. Such isocyanate intermediates correspond to the generalformula represented in reaction sequences IV and V set forthhereinbefore. Such novel intermediates are prepared according to theteachings of the specification and representative examples 6 and 7,which also set forth the nomenclature of such compounds. The novelacetamide intermediates, which are useful as intermediates in preparingthe corresponding novel amine intermediates and which also have utilityas herbicides, include those which correspondingly are employed toprepare the readily apparent amine intermediates, in turn used inpreparing the compounds enumerated above. Such acetamide compoundscorrespond to the formula set forth in reaction sequence I and areprepared according to the teachings of the specification and Examples1-3, wherein the nomenclature for such compounds is set forth.

The compounds of the present invention have been found to be suitablefor use in methods for the pre- and post-emergent control of weeds orother unwanted vegetation. Certain of the active ingredients of thepresent invention have been found to be active against undesiredvegetation in the presence of desired crop plants while producing only anegligible effect on the crop plants. For all such uses, unmodifiedactive ingredients of the present invention can be employed. However,the present invention embraces the use of a herbicidally effectiveamount of the active ingredients in composition form with a materialknown in the art as an adjuvant or carrier in solid or liquid form.Thus, for example, an active ingredient can be dispersed on a finelydivided solid and employed therein as a dust. Also, the activeingredients, as liquid concentrates or solid compositions comprising oneor more of the active ingredients, can be dispersed in water, typicallywith the aid of a wetting agent, and the resulting aqueous dispersionemployed as a spray. In other procedures, the active ingredient can beemployed as a constituent of organic liquid compositions, oil-in-waterand water-in-oil emulsions, or water dispersions, with or without theaddition of wetting, dispersing, or emulsifying agents.

Suitable adjuvants of the foregoing type are well known to those skilledin the art. The methods of applying the solid or liquid herbicidalformulations similarly are well known to the skilled artisan.

As organic solvents used as extending agents there can be employedhydrocarbons, e.g., benzene, toluene, xylene, kerosene, diesel fuel,fuel oil, and petroleum naphtha, ketones such as acetone, methyl ethylketone and cyclohexanone, chlorinated hydrocarbons such as carbontetrachloride, chloroform, trichloroethylene, and perchloroethylene,esters such as ethyl acetate, amyl acetate and butyl acetate, ethers,e.g., ethylene glycol monomethyl ether and diethylene glycol monomethylether, alcohols, e.g., methanol, ethanol, isopropanol, amyl alcohol,ethylene glycol, propylene glycol, butyl Carbitol acetate and glycerine.Mixtures of water and organic solvents, either as solutions oremulsions, can be employed.

The active ingredients can also be applied as aerosols, e.g., bydispersing them in air by means of a compressed gas such asdichlorodifluoromethane or trichlorofluoromethane and other Freons andGenetrons, for example.

The active ingredients of the present invention can also be applied withadjuvants or carriers such as talc, pyrophyllite, synthetic fine silica,attapulgus clay, keiselguhr, chalk, diatomaceous earth, lime, calciumcarbonate, bentonite, fuller's earth, cottonseed hulls, wheat flour,soybean flour, pumice, tripoli, wood flour, walnut shell flour, redwoodflour and lignin.

As stated, it is frequently desirable to incorporate a surface activeagent in the compositions of the present invention. Such surface activeor wetting agents are advantageously employed in both the solid andliquid compositions. The surface active agent can be anionic, cationicor nonionic in character.

Typical classes of surface active agents include alkyl sulfonate salts,alkylaryl sulfonate salts, alkylaryl polyether alcohols, fatty acidesters of polyhydric alcohols and the alkylene oxide addition productsof such esters, and addition products of long chain mercaptans andalkylene oxides. Typical examples of such surface active agents includethe sodium alkylbenzene sulfonates having 10 to 18 carbon atoms in thealkyl group, alkylphenol ethylene oxide condensation products, e.g.,p-isooctylphenol condensed with 10 ethylene oxide units, soaps, e.g.,sodium stearate and potassium oleate, sodium salt of propylnapthalenesulfonic acid, di(2-ethylhexyl)ester of sodium sulfosuccinic acid,sodium lauryl sulfate, sodium decane sulfonate, sodium salt of thesulfonated monoglyceride of coconut fatty acids, sorbitan sesquioleate,lauryl trimethyl ammonium chloride, octadecyl trimethyl ammoniumchloride, polyethylene glycol lauryl ether, polyethylene glycol estersof fatty acids and rosin acids, e.g. Ethofat 7 and 13, sodiumN-methyl-N-oleyl taurate, Turkey Red Oil, sodium dibutyl naphthalenesulfonate, sodium lignin sulfonate, polyethylene glycol stearate, sodiumdodecylbenzene sulfonate, tertiary dodecyl polyethylene glycol thioether(nonionic 218), long chain ethylene oxidepropylene oxide condensationproducts, e.g., Pluronic 61 (molecular weight 1000), polyethylene glycolester of tall oil acids, sodium octyl phenoxyethoxyethyl sulfate,tris-(polyoxyethylene)sorbitan monostearate (Tween 60), and sodiumdihexyl sulfosuccinate.

The concentration of the active ingredients in liquid compositionsgenerally is from about 0.001 to about 95 percent by weight or more.Concentrations of from about 0.001 to about 50 weight percent are oftenemployed. In dusts or dry formulations, the concentration of the activeingredient can be from about 0.001 to about 95 weight percent or more;concentrations of from about 0.001 to about 50 weight percent are oftenconveniently employed. In compositions to be employed as concentrates,the active ingredient can be present in a concentration of from about 5to about 98 weight percent. The active ingredient compositions can alsocontain other compatible additaments, for example, phytotoxicants, plantgrowth regulants, pesticides and the like and can be formulated withsolid particulate fertilizer carriers such as ammonium nitrate, urea andthe like.

The present compositions can be applied by the use of power-dusters,boom and hand sprayers, spray-dusters, by addition to irrigation water,and by other conventional means. The compositions can also be appliedfrom airplanes as a dust or a spray because they are effective in verylow dosages.

The exact dosage to be applied is dependent not only upon the specificactive ingredient being employed, but also upon the particular plantspecies to be modified and the stage of growth thereof, as well as thepart of the plant to be contacted with the toxic active ingredient.Thus, it is to be understood that all of the active ingredients of theinvention and compositions containing the same may not be equallyeffective at similar concentrations or against the same plant species.In non-selective pre-emergence and foliage treatments the compositionsof this invention are usually applied at an approximate rate of fromabout 1 to about 25 lbs. per acre, but lower or higher rates may beappropriate in some cases. In selective post-emergence operations tofoliage, a dosage of from about 0.16 to about 5.0 pounds per acre isusually employed. In some instances, lower dosages may be utilized whilehigher dosages may be necessary in other instances. In view of theforegoing and following disclosures, one skilled in the art can readilydetermine the optimum rate to be applied in any particular case.

So as to illustrate the general and selective phytotoxic properties ofthe active ingredients of the present invention, a group of controlledgreenhouse experiments is described below. In such operations, thevarious seeds and plants employed are represented by letters as follows:

    A. German Millet  M. Rice                                                     B. Foxtail        N. Wheat                                                    C. Barnyard Grass O. Corn                                                     D. Crabgrass      P. Soybean                                                  E. Johnson Grass  Q. Cotton -F. Wild oat R. Sorghum                           G. Pigweed        S. Coffee weed                                              H. Bindweed       T. Prickly Sida                                             I. Velvet leaf    U. Ground Cherry                                            J. Morning Glory  V. Lambsquarter                                             K. Wild Mustard   W. Jimson Weed                                              L. Cocklebur                                                              

In pre-emergence operations, seeds of selected species are planted inseedbeds and, while exposed, sprayed with a given volume of a solutioncontaining a predetermined amount of the candidate active ingredient toprovide the dosage rate desired. Such compositions are prepared bymixing the selected active ingredient and an emulsifier or dispersantwith water. The seeds are then covered with a layer of soil andmaintained under conditions conducive to growth. A portion of theplanted seedbeds are left untreated to provide controls for comparativepurposes. All seedbeds are watered from below as needed. About 14 daysafter seeding and treating, the effect of each of the test ingredientson the seeds is evaluated by a comparison with the control seedbeds.

In post-emergence operations, various species of plants are seeded inbeds of good agricultural soil. After the plants have emerged and grownto a height of from about 2 to 6 inches, certain of the plants aresprayed to run-off with a given volume of a composition prepared as setforth above. Other plants are left untreated to provide comparativecontrols. All plants are maintained as above for a period of about 14days and then evaluated to determine the effect of each test ingredient.

In representative general pre-emergence operations, each of theN'-(4-(((6-trifluoromethyl)-2-pyridyl)oxy)phenyl)-N,N-dimethyl urea(Compound 1);N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N-methoxy-N-methylurea (Compound 2);N'-(4-((6-bromo-2-pyridinyl)oxy)phenyl)-N-methoxy-N-methyl urea(Compound 3);N-methoxy-N-methyl-N'-((((6-trifluoromethyl)-2-pyridinyl)oxy)phenyl)urea(Compound 4);N'-(4-((6-(chlorodifluoromethyl)-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea (Compound 5) andN'-(4-((6-fluoro-2-pyridinyl)oxy)phenyl)-N-methoxy-N-methyl urea(Compound 6) compounds was found to give substantial (at least 70%) tocomplete (100%) inhibition of the growth of plant species A, C, D, E, F,G, H, I, J, and K at a dosage rate of approximately 5.0 pounds per acre.In similar general operations, each of theN'-(4-((4,6-dimethyl-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea (Compound7) andN'-(4-((5-chloro-6-cyano-2-pyridinyl)oxy)phenyl)-N-methoxy-N-methyl urea(Compound 8) compounds was found to give substantial to completeinhibition of growth of species A, E, G and K at a dosage rate of 5.0pounds per acre.

In representative selective pre-emergence operations, it was found thatN'-(4-((6-chloro-2-pyridinyl)thio)phenyl)-N,N-dimethyl urea (Compound9), Compound 1, Compound 2, Compound 3, Compound 4 and Compound 5 eachgives from 90 to 100% control of the growth of pigweed seeds with littleor no inhibition on the growth of desirable crop seeds such as soybeans(P), corn (O) and cotton (Q) at a dosage rate of about 0.6 pounds peracre. In other operations, it was found thatN'-(4-((5-chloro-6-cyano-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea(Compound 10) gave complete control of the growth of species (D) and (G)with no inhibition on the growth of desirable crop species (O), (Q) and(R) at an application rate of about 1.25 pounds per acre.

In additional pre-emergence operations, each of theN'-((4-(6-bromo-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea (Compound 11),N'-(4((6-chloro-4-(trifluoromethyl)-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea (Compound 12),N,N-dimethyl-N'-(4-((6-methyl-2-pyridinyl)oxy)phenyl)urea (Compound 13),N'-(4-((6-chloro-4-(trifluoromethyl)-2-pyridinyl)oxy)phenyl)-N-methoxy-N-methylurea (Compound 14),N-butyl-N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N-methyl urea (Compound15), N,N-dimethyl-N'-(4-((4-methyl-2-pyridinyl)oxy)phenyl)urea (Compound16),N-((4-chlorophenyl)thio)-N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N-methylurea (Compound 17) and Compound 7 was found to give complete control of,inter alia, species (D), (G) and (I) at dosage rates of about 10 poundsper acre.

In representative general post-emergence operations, each ofN'-(4-((3,5,6-trichloro-2-pyridyl)oxy)phenyl)-N,N-dimethyl urea(Compound 18) and N'-(4-((3-cyano-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea (Compound 19) was found to give complete control of (G) at a dosagerate of about 10 pounds per acre.N'-(4-((6-Chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea (Compound 20)was similarly found to be effective in the post-emergence control of (I)while N'-(4-((6-bromo-2-pyridinyl)thio)phenyl)-N,N-dimethyl urea(Compound 21) was found to give substantial control of (A), (C), (D),(G), (H), and (I), at dosage rates of about 10 pounds per acre,respectively.

In additional operations, each of Compounds 9, 13, 14, 15 and 16 andN,N-dimethyl-N'-(4-(2-pyridinyloxy)phenyl)urea (Compound 22),N'-(4-((3,5-dichloro-6-fluoro-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea(Compound 23),N'-(4-((4-chloro-6-(trifluoromethyl)-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea (Compound 24),N,N'dimethyl-N'-(4-((6-(propylthio)-2-pyridinyl)oxy)phenyl)urea(Compound 25),N'-(4-((6-chloro-2-pyridyl)oxy)-3-(trifluoromethyl)phenyl)-N,N-dimethylurea (Compound 26),N,N-dimethyl-N'-(4-((6-(trifluoromethyl)-2-pyridinyl)thio)phenyl)urea(Compound 27), N,N-dimethyl-N'-(4-((6-propoxy)-2-pyridyl)oxy)phenyl)urea(Compound 28),N'-(4-((6-chloro-2-pyridinyl)thio)phenyl)-N-methoxy-N-methyl urea(Compound 29), N'-(4-((6-fluoro-2-pyridinyl)thio)phenyl)-N,N-dimethylurea (Compound 30),N-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-2,5-dimethyl-1-pyrrolidinecarboxamide(Compound 31),N'-(4-((6-chloro-4-(chlorodifluoromethyl)-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea (Compound 32) andN'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethylthiourea (Compound33) were found to be effective as post-emergence herbicides at a dosagerate of about 10.0 pounds per acre. The post-emergence activity is setforth in the following Table I.

                  Table I                                                         ______________________________________                                        Plant Type/Percent Control                                                    ______________________________________                                        Cmpd.                                                                         No.   A       C       D     E    G    H    I    J                             ______________________________________                                        9     100     100     100   25   0    0    100  100                           13    100     100     100   35   100  100  100  100                           14    100     100     100   0    100  100  100  100                           15    100     100     100   100  100  100  100  100                           16    100     100     100   --   100  100  100  100                           22    100     100     100   100  100  --   100  100                           23    100     35      100   20   20   40   30   100                           24    100     100     100   100  100  100  100  100                           25    0       100     40    0    100  100  100  35                            26    100     100     100   100  100  100  100  100                           27    100     100     100   100  100  100  100  100                           28    100     100     100   100  40   50   100  100                           29    100     100     30    35   100  100  100  100                           30    100     100     100   50   100  100  100  100                           31    100     100     100   25   --   100  100  100                           32    100     100     100   100  100  100  100  100                           33    100     100     100   100  100  100  100  100                           ______________________________________                                    

Additional post-emergence operations employing compounds (1), (2), (4),(5), (10), (11), (12),N,N-dimethyl-N'-(4-((3,6-dichloro-2-pyridinyl)oxy)phenyl)urea (Compound34), N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea(Compound 35),N'-(4-((5-chloro-6-cyano-2-pyridinyl)thio)phenyl)-N,N-dimethyl urea(Compound 36), N'-(4-((6-fluoro-2-pyridyl)oxy)phenyl)-N,N-dimethyl urea(Compound 37), N'-((3-(6-fluoro-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea (Compound 38),N'-(3-((6-(trifluoromethyl)-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea(Compound 39), N'-((3-(6-chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea (Compound 40),N'-(4-((4,6-bis(trifluoromethyl)-2-pyridinyl)oxy)phenyl-N,N-dimethylurea (Compound 41),N,N-dimethyl-N'-(4-((6-(methylthio)-2-pyridinyl)oxy)phenyl)urea(Compound 42), N,N-dimethyl-N'-(4-((5-nitro-2-pyridinyl)oxy)phenyl)urea(Compound 43), N'-((4-(6-cyano-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea(Compound 44), N'-(4-((5-chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea (Compound 45),N'-((4-(6-fluoro-2-pyridinyl)oxy)phenyl)-N-methylurea (Compound 46),N'-(4-((6-fluoro-2-pyridinyl)oxy)phenyl)-N,N-dimethylthiourea (Compound47), N'-(4-((6-methoxy-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea(Compound 48), N'-(4-((3-chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethylurea (Compound 49),N'-(4-((3,5-dichloro-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea (Compound50), N'-((3-(5-chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea(Compound 51), N'-(4-((6-iodo-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea(Compound 52),N'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N-methoxy-N-methoxy-N-methylthiourea(Compound 53),N-butyl-N'-(4((6-chloro-2-pyridinyl)oxy)phenyl)-N-methylthiourea(Compound 54), andN'-(4-((6-bromo-2-pyridinyl)oxy)phenyl)-N,N-dimethylthiourea (Compound55) against various plant species is reported in the following Table II.The data also indicate the selective activity of several compounds inthe presence of desired crop plants at lower dosage rates.

                                      TABLE II                                    __________________________________________________________________________    Dos-                                                                          age    Plant Species/% Control                                                Cmpd.                                                                             lbs/                                                                             Weeds                                           Crops                  No. Acre                                                                             A  B  C  D  E  G  H  I  J  K  L  S  T  U  V  W  N O  P                 __________________________________________________________________________    1a. 5.0                                                                              -- 100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              -- -- 100                                                                              100                                                                              100                                                                              -- -- -- --    90                                                                              100                                                                              100               b.  .63                                                                              100                                                                              100                                                                              100                                                                              100                                                                              90 100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              0     40                                                                      100                    c.  .16                                                                              50 95 100                                                                              100                                                                              30 90 40 100                                                                              70 100                                                                              100                                                                              100                                                                              100                                                                              90 100                                                                              70 0     0                                                                       60                     2a. 2.5                                                                              100                                                                              -- 100                                                                              -- -- 100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              90 100                                                                              100                                                                              40    20                                                                      100                    b.  .63                                                                              50 -- 50 -- -- 100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              50 100                                                                              100                                                                              0     0                                                                       100                    c.  .16                                                                              50 -- 50 -- -- 100                                                                              50 100                                                                              100                                                                              100                                                                              100                                                                              60 100                                                                              0  100                                                                              70 0     0                                                                       0                      4a. 2.5                                                                              -- 100                                                                              100                                                                              -- -- 100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              90 100                                                                              100                                                                              50    70                                                                      100                    b.  .63                                                                              -- 100                                                                              100                                                                              -- -- 100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              90 100                                                                              100                                                                              0     20                                                                      80                     c.  .16                                                                              -- 50 70 -- -- 100                                                                              100                                                                              100                                                                              90 100                                                                              100                                                                              90 70 0  100                                                                              60 0     0                                                                       60                     5a. 2.5                                                                              -- -- -- -- -- 100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              -- 100                                                                              100                                                                              90 100                                                                              -- 10    40                                                                      100                    b.  .63                                                                              -- -- -- -- -- 50 100                                                                              80 100                                                                              100                                                                              -- 100                                                                              100                                                                              70 100                                                                              -- 0     0                                                                       80                     c.  .16                                                                              -- -- -- -- -- 0  0  30 40 100                                                                              -- 100                                                                              30 0  100                                                                              -- 0     0                                                                       60                     8a. 2.5                                                                              0  -- 90 -- -- 100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              50 100                                                                              100                                                                              0  100                                                                              50 0     0                                                                       20                     b.  .63                                                                              0  -- 50 -- -- 100                                                                              0  50 50 90 50 100                                                                              50 0  100                                                                              0  0     0                                                                       0                      c.  .16                                                                              0  -- 0  -- -- 50 0  0  0  50 0  20 0  0  0  0  0     0                                                                       0                      10a.                                                                              2.5                                                                              -- -- -- -- -- 100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              -- 100                                                                              100                                                                              70 100                                                                              -- 10    60                                                                      100                    b.  .16                                                                              -- -- -- -- -- 100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              -- 100                                                                              20 0  100                                                                              -- 0     0                                                                       20                     11a.                                                                              2.5                                                                              -- 100                                                                              100                                                                              100                                                                              90 100                                                                              -- -- 100                                                                              100                                                                              100                                                                              -- -- -- -- -- 0     10                                                                      100                    b.  .16                                                                              -- 100                                                                              100                                                                              40 0  40 -- -- 100                                                                              100                                                                              100                                                                              -- -- -- -- -- 0     0                                                                       20                     12a.                                                                              5.0                                                                              100                                                                              100                                                                              100                                                                              100                                                                              50 100                                                                              70 70 -- 100                                                                              100                                                                              -- -- -- -- -- 0     0                                                                       100                    b.  .63                                                                              90 90 100                                                                              100                                                                              30 100                                                                              60 40 -- 100                                                                              0  -- -- -- -- -- 0     0                                                                       40                     21a.                                                                              2.5                                                                              30 -- 100                                                                              -- -- 100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              50 0  100                                                                              100                                                                              0     0                                                                       100                    b.  .16                                                                              0  -- 10 -- -- 0  50 100                                                                              100                                                                              100                                                                              0  100                                                                              0  0  0  0  0     0                                                                       0                      22 .                                                                              1.25                                                                             -- 40 0  0  0  10 -- -- 20 100                                                                              0  -- -- -- -- -- 0     0                                                                       80                     34a.                                                                              2.5                                                                              90 -- 100                                                                              -- -- 100                                                                              50 100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              100                                                                              20 100                                                                              50 0     10                                                                      70                     b.  .63                                                                              70 -- 50 -- -- 50 0  20 70 100                                                                              50 100                                                                              100                                                                              0  100                                                                              0  0     0                                                                       20                     35a.                                                                              2.5                                                                              100                                                                              100                                                                              100                                                                              100                                                                              90 100                                                                              100                                                                              85 100                                                                              100                                                                              100                                                                              -- -- -- -- -- 60    80                                                                      100                    b.  .63                                                                              100                                                                              100                                                                              100                                                                              100                                                                              60 100                                                                              70 75 100                                                                              100                                                                              100                                                                              -- -- -- -- -- 20    40                                                                      100                    c.  .16                                                                              90 90 60 90 60 60 40 40 50 100                                                                              50 -- -- -- -- -- 0     0                                                                       40                     36a.                                                                              10.0                                                                             100                                                                              -- 100                                                                              -- -- 100                                                                              60 95 100                                                                              100                                                                              30 100                                                                              100                                                                              30 100                                                                              100                                                                              0     0                                                                       100                    b.  2.5                                                                              80 -- 50 -- -- 0  40 30 100                                                                              100                                                                              30 0  50 0  100                                                                              20 0     0                                                                       50                     37a.                                                                              1.25                                                                             -- 90 100                                                                              100                                                                              80 100                                                                              -- -- 90 100                                                                              100                                                                              -- -- -- -- -- 0     50                                                                      95                     b.  0.16                                                                             -- 0  0  90 0  100                                                                              -- -- 0  50 0  -- -- -- -- -- 0     0                                                                       10                     38a.                                                                              2.5                                                                              -- 95 100                                                                              100                                                                              70 90 -- -- 100                                                                              100                                                                              100                                                                              -- -- -- -- -- 0     20                                                                      100                    b.  0.63                                                                             -- 20 60 100                                                                              20 50 -- -- 50 95 50 -- -- -- -- -- 0     0                                                                       20                     39a.                                                                              1.25                                                                             -- 100                                                                              100                                                                              100                                                                              100                                                                              70 -- -- 100                                                                              100                                                                              100                                                                              -- -- -- -- -- 10    50                                                                      100                    b.  0.32                                                                             -- 100                                                                              40 50 100                                                                              30 -- -- 80 100                                                                              100                                                                              -- -- -- -- -- 0     20                                                                      80                     40a.                                                                              2.5                                                                              -- 95 95 100                                                                              30 50 -- -- 90 100                                                                              50 -- -- -- -- -- 0     0                                                                       60                     b.  .63                                                                              -- 0  80 100                                                                              10 0  -- -- 20 50 0  -- -- -- -- -- 0     0                                                                       0                      41a.                                                                              1.25                                                                             -- 100                                                                              100                                                                              100                                                                              50 100                                                                              -- -- 90 100                                                                              100                                                                              -- -- -- -- -- 10    30                                                                      90                     b.  .32                                                                              -- 90 40 90 0  50 -- -- 50 90 60 -- -- -- -- -- 0     0                                                                       20                     42a.                                                                              5.0                                                                              -- 100                                                                              100                                                                              80 0  70 -- -- 90 100                                                                              100                                                                              -- -- -- -- -- 0     0                                                                       50                     b.  1.25                                                                             -- 80 90 0  0  40 -- -- 60 100                                                                              0  -- -- -- -- -- 0     0                                                                       10                     43a.                                                                              10.0                                                                             -- 0  70 0  0  60 -- -- 100                                                                              100                                                                              100                                                                              -- -- -- -- -- 0     0                                                                       30                     b.  0.63                                                                             -- 0  0  0  0  0  -- -- 0  100                                                                              0  -- -- -- -- -- 0     0                                                                       0                      44a.                                                                              10.0                                                                             -- 100                                                                              100                                                                              100                                                                              0  90 -- -- 100                                                                              100                                                                              100                                                                              -- -- -- -- -- 0     0                                                                       100                    b.  1.25                                                                             -- 95 90 0  0  50 -- -- 100                                                                              70 70 -- -- -- -- -- 0     0                                                                       100                    45a.                                                                              1.25                                                                             -- 90 100                                                                              90 70 100                                                                              -- -- 100                                                                              100                                                                              100                                                                              -- -- -- -- -- 10    40                                                                      100                    b.  0.32                                                                             -- 90 100                                                                              90 50 90 -- -- 100                                                                              100                                                                              50 -- -- -- -- -- 0     0                                                                       100                    46a.                                                                              10.0                                                                             -- 100                                                                              100                                                                              100                                                                              0  70 -- -- 0  100                                                                              100                                                                              -- -- -- -- -- 0     0                                                                       100                    b.  2.5                                                                              -- 70 80 90 0  100                                                                              -- -- 0  100                                                                              50 -- -- -- -- -- 0     0                                                                       80                     47a.                                                                              10.0                                                                             100                                                                              70 70 60 60 100                                                                              70 100                                                                              100                                                                              95 70 -- -- -- -- -- 20    20                                                                      100                    b.  1.25                                                                             70 40 50 50 10 80 40 80 80 100                                                                              0  -- -- -- -- -- 0     0                                                                       70                     48a.                                                                              10.0                                                                             100                                                                              100                                                                              100                                                                              100                                                                              60 90 90 100                                                                              100                                                                              100                                                                              100                                                                              -- -- -- -- -- 20    10                                                                      100                    b.  1.25                                                                             95 95 60 70 20 50 20 60 80 100                                                                              70 -- -- -- -- -- 0     0                                                                       60                     49  5.0                                                                              70 50 40 70 0  80 10 50 90 90 10 -- -- -- -- -- 0     0                                                                       40                     50a.                                                                              5.0                                                                              90 80 80 100                                                                              50 100                                                                              60 60 95 90 70 -- -- -- -- -- 0     0                                                                       40                     b.  0.63                                                                             60 50 20 80 20 100                                                                              40 0  20 100                                                                              0  -- -- -- -- -- 0     0                                                                       0                      51a.                                                                              1.25                                                                             -- 100                                                                              100                                                                              100                                                                              80 100                                                                              -- -- 100                                                                              100                                                                              100                                                                              -- -- -- -- -- 20    40                                                                      70                     b.  0.32                                                                             -- 40 80 100                                                                              30 50 -- -- 40 100                                                                              50 -- -- -- -- -- 0     0                                                                       20                     52a.                                                                              10.0                                                                             100                                                                              -- 80 100                                                                              0  100                                                                              100                                                                              25 100                                                                              -- -- -- -- -- -- -- --    0                                                                       25                     b.  0.63                                                                             55 -- 0  30 0  100                                                                              90 0  45 -- -- -- -- -- -- -- --    0                                                                       0                      53a.                                                                              10.0                                                                             90 -- 100                                                                              100                                                                              20 100                                                                              100                                                                              30 95 -- -- -- -- -- -- -- --    0                                                                       90                     b.  1.25                                                                             30 -- 90 70 0  100                                                                              100                                                                              0  100                                                                              -- -- -- -- -- -- -- --    0                                                                       30                     __________________________________________________________________________

In further operations, each of theN-(4-((6-chloro-2-pyridinyl)oxy)phenyl)propanamide,N-(3-chloro-4-((6-chloro-2-pyridinyl)oxy)phenyl)propanamide,N-(4-((6-chloro-2-pyridinyl)oxy)phenyl)acetamide andN-(4-((6-fluoro-2-pyridinyl)oxy)phenyl)acetamide compounds was found togive substantial to complete pre- and post-emergence control ofcrabgrass at a dosage rate about 10.0 pounds per acre.

In additional post-emergence operations, each ofN'-((4-(5-cyano-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea (Compound 56)and N'-(4-((6-chloro-5-cyano-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea(Compound 57) was found to give complete control of species (A), (I) and(J) at a dosage rate of about 10.0 pounds per acre.

The foregoing data illustrate the general phytotoxic activity as well asselective phytotoxic activity of the compounds of the present invention.Although selective pre- and post- emergence activity has beendemonstrated at several rates of application, it is to be understoodthat further specific selective operations and crop specificity are inmany instances, obtainable by employing lower dosage rates thandemonstrated above.

The substituted halopyridine, acetamidophenate, carbamoyl halide,nitro(thio)phenol, hydroxylamine, pyrrolidine and piperidine reactantsemployed in the present invention are either readily available or can beprepared according to procedures which are known or are analogous tothose set forth in the open literature.

Although the invention is described with respect to specific embodimentsand modifications, the details thereof are not to be construed aslimitations except to the extent indicated in the following claims:

I claim:
 1. A compound corresponding to the formula: ##SPC9##wherein:each p independently represents an integer of 0 or 1; each Xindependently represents bromo, chloro, iodo or fluoro; m represents aninteger of 0 to 4, inclusive; each Y independently represents nitro,ZR³, --C(X')₃ or ##EQU11## n represents an integer of 0 to 2, inclusive;each Z independently represents oxygen or sulfur; Q represents methyl,ethyl, halo, nitro or trifluoromethyl; each X' independently representshydrogen or halo; R¹ represents hydrogen, alkyl of from 1 to 4 carbonatoms or alkoxy of from 1 to 4 carbon atoms; R² represents alkyl of from1 to 3 carbon atoms or ##SPC10## R³ represents alkyl of from 1 to 3carbon atoms; R⁴ and R⁵ each independently represent hydrogen or alkylof from 1 to 4 carbon atoms; and each R⁶ represents halo or alkyl offrom 1 to 3 carbon atoms.
 2. The compound of claim 1 wherein n is 0 andm is at least
 1. 3. The compound of claim 1 wherein m is 0 and n is atleast
 1. 4. The compound of claim 1 wherein the sum of n + m is one andX or Y is substituted on the 6-ring position.
 5. The compound of claim 1wherein m is 1, n is 0, X is substituted in the 6-ring position of thepyridine moiety.
 6. The compound of claim 1 wherein m is 0, n is 1 and Yis substituted in the 6-ring position of the pyridine moiety.
 7. Thecompound of claim 1 wherein R¹ and R² each represent alkyl.
 8. Thecompound of claim 1 wherein R¹ is alkoxy and R² is alkyl.
 9. Thecompound of claim 1 which isN'-(4-((6-(trifluoromethyl)-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea.10. The compound of claim 1 which isN'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N-methoxy-N-methyl urea. 11.The compound of claim 1 which isN'-(4-((6-chloro-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea.
 12. Thecompound of claim 1 which isN'-(4-((6-chloro-2-pyridinyl)thio)phenyl)-N-methoxy-N-methyl urea. 13.The compound of claim 1 which isN-methoxy-N-methyl-N'-((6-trifluoromethyl)-2-pyridinyl)oxy)phenyl) urea.14. The compound of claim 1 which isN'-(4-((6-bromo-2-pyridinyl)oxy)phenyl)-N,N-dimethyl urea.